[gnome-shell] switchMonitor: switch to next config upon initial keypress

[Florian Müllner <fmuellner src gnome org>]

commit fcdac69eea101e1c09c2b70647f562077517380b
Author: Daniel Drake <drake endlessm com>
Date:   Mon Jul 30 21:17:44 2018 -0300

    switchMonitor: switch to next config upon initial keypress
    
    In GNOME-3.24, pressing Super+P or a similar function key would cause
    a switch to the next available monitor configuration.
    
    However, in GNOME-3.26, this was reimplemented in mutter and gnome-shell
    and the behaviour is now different: pressing Super+P and releasing will
    cause no change in montor configuration[1]. In this new design you have
    to press Super+P and keep holding Super in order to keep the switcher
    open, then press P again (or use the arrow keys or mouse) to
    select the next one in the list.
    
    This is incompatible with many Asus products such as Asus X530UN, where
    pressing the presentation mode media key (Fn+F8) actually generates
    the following keypress events from the keyboard controller:
    
    Fn pressed: nothing
    F8 pressed: nothing
    F8 released: Super press, p press, p release, Super release (quick burst)
    Fn released: nothing
    
    With this firmware behaviour it's not possible to hold the keys and have
    the dialog come up so that you can select another new mode.
    
    To solve this, when the switcher is opened, select the next available
    display config by default, which is more similar to the pre-GNOME-3.26
    behaviour. Now pressing Fn+F8 on this laptop will result in the display
    mode switch taking place.
    
    [1]: The mentioned desired behaviour will at least happen after
    https://gitlab.gnome.org/GNOME/mutter/issues/281 has been fixed
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/208

 js/ui/switchMonitor.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/js/ui/switchMonitor.js b/js/ui/switchMonitor.js
index 96fb85407..31b4f3376 100644
--- a/js/ui/switchMonitor.js
+++ b/js/ui/switchMonitor.js
@@ -49,8 +49,8 @@ var SwitchMonitorPopup = new Lang.Class({
 
     _initialSelection() {
         let currentConfig = Meta.MonitorManager.get().get_switch_config();
-        currentConfig %= Meta.MonitorSwitchConfigType.UNKNOWN;
-        this._select(currentConfig);
+        let selectConfig = (currentConfig + 1) % Meta.MonitorSwitchConfigType.UNKNOWN;
+        this._select(selectConfig);
     },
 
     _keyPressHandler(keysym, action) {